The present disclosure relates to methods and apparatus that employ blockchain systems.
Blockchain systems are sometimes referred to as global state systems wherein global states are stored across a distributed number of devices via the Internet. A combination of public/private key cryptography and hash chains provide a mechanism to store arbitrary secure states as a single ledger (i.e., the blockchain) held at all distributed nodes. Nodes may update their local state based on a consensus algorithm applied to the system as a whole. Blockchain systems are also referred to as distributed ledger systems and can facilitate real time and secure data sharing. Some system examples include Ripple, Multichain and the Hyper Ledger Project. Digitally recorded “blocks” of data are stored in a linear chain. Each block in a chain contains data which can include a transaction which is cryptographically hashed. The blocks of hashed data draw upon the previous hashed block which comes before in the chain, insuring illegitimate modifications to the data can be detected and rejected.
In the global or public transaction blockchain systems such as bitcoin, typically no source attribution is provided, they are pseudonymous. In contrast, permission based blockchain systems, i.e., those that require participants to have permission to read and/or write to the block chain, may use source attribution data which may provide more control amongst participants, such as originators of transactions, recipients of transactions, and other entities that create and access the blockchain. However, known permission based blockchain systems may not provide effective source attribution security that can be required for blockchains that require enhanced security thereby exposing the block chain to fraudulent impersonation of originators and/or recipients resulting in, inter alia, data theft.